12au7’s, correct?
There is an overwhelming amount of choices ranging from around $60-$600 a pair and more. Some of the more popular NOS brands are Amperex, Mullard, Telefunken, Cifte, Tung-Sol, just to name a few. You can go to sites like Brent Jesse and read about the attributes of each and pricing.
Personally, I like Amperex best, but of course it’s going to boil down to your gear and your ear. I have no experience with new issue tubes. Do a little research, establish a starting budget, and jump on in!